Sampling procedure
<p style="border:solid thin black;"> THE CLEANED AND HARMONIZED VERSION OF THE SURVEY DATA PRODUCED AND PUBLISHED BY THE ECONOMIC RESEARCH FORUM REPRESENTS 100% OF THE ORIGINAL SURVEY DATA COLLECTED BY THE PALESTINIAN CENTRAL BUREAU OF STATISTICS</p>
The methodology was designed according to the context of the survey, international standards, data processing requirements and comparability of outputs with other related surveys.
---> Target Population:
It consists of all Palestinian households and individuals who habitually reside with their households in Palestine for the reference period of the survey, which is 2020, and there was a focus on individuals of the age group 18 years and over to complete an additional form for individuals in this category.
---> Sampling Frame:
The sampling frame consists of a comprehensive sample selected from the Population, Housing and Establishments Census 2017: This comprehensive sample consists of geographical areas with an average of 150 households, and these are considered as enumeration areas used in the census and these units were used as primary sampling units (PSUs).
---> Sampling Size:
The estimated sample size is 3623 households in 2020.
---> Sample Design
The sample is two stage stratified cluster sample with three stages :
First stage: a systematic random sample of 161 enumeration areas for the whole round was selected.
Second stage: choosing (9-25) households from each enumeration area in the first stage in a systematic random manner.
Third stage: a male or female individual was selected from all sample families (old and new) in the second stage of individuals 18 years and over using check tables to complete the form for individuals 18 years and over (quality of life model). Taking into account that the household whose number is even in the enumeration area sample, we choose a female from it, and the household whose number is odd, from which we choose a male. In Jerusalem, Area J1, area sample of 25 households was selected from each enumeration area in the first stage.
---> Sample strata:
The population was divided by:
1. The governorate (16 governorates in the West Bank, including Jerusalem J1 governorate, which the Israeli occupation annexed to it by force after its occupation of the West Bank in 1967 as Tabqa and the Gaza Strip).
2. Type of settlement (urban, rural, camp).
3. Area C (class C, non-C) as an implicit class.
Response rates
The survey sample consists of about 3623 households of which 3122 households completed the interview; whereas 2104 households from the West Bank and 1018 households in Gaza Strip. Weights were modified to account for non-response rate. The response rate in the West Bank reached 85.5% while in the Gaza Strip it reached 87.6%.
Weighting
The weight of statistical units (sampling unit) in the sample is defined as the mathematical inverse of the selection probability where the sample of the survey is a three-stage stratified cluster systematic random sample. In the first stage, the weight of enumeration areas is calculated based on the probability of each enumeration area. In the second stage, the weight of households in each enumeration area is calculated. Initial household weights resulted from the product of the weight of the first stage and the weight of the second stage. Then the initial weight is adjusted by producing the initial weight and the attrition factor (attrition from the sample). The final household weights were obtained after adjustment of the initial weights with the household estimates for mid-2020 according to design strata (governorate, locality type).
Weights of households members’ portfolio are calculated by giving every member the final weight of his/her household, which is the primary individual/member weight. Primary Individual/Member’s Weight is then adjusted according to area, gender and age groups (17 groups) representing the age of individual/member by mid-December 2020. This enabled to obtain the individual/member’s final weight in his/her category. The weights are then merged in the individual/member’s portfolio for individuals aged 18 and above.